The device and method of the present invention relate to a frame assembly that is constructed and arranged for use in screen printing operations. Particularly, this invention relates to a method of constructing a frame assembly to which a taut screen is attached for use in textile screen printing presses. More particularly this invention relates to the use of known electrical conduit for purposes of making print screen frame assemblies.
The electrical conduit formed frame assembly of the invention is comprised of coated metal conduit that is formed into a predetermined shape or frame configuration. The method of manufacturing the printing frame assembly includes providing at least one length of electrical conduit, bending the conduit to form a planar enclosure and joining the conduit by means of at least one insert. Attached to the electrical conduit or coated metallic frame can be at least one spacer used for mounting the frame to a printing press and for stacking the frames for storage purposes. The spacers may be coded for identifying the frames from one another.
In the past, print screen frames have generally been found to either lack durability or to be expensive. Prior art frames have been found to easily warp, to bow, or to separate at the corners during use, for example. Prior art frames are typically constructed of wood or other non-durable materials. Such prior art frames are heavy, easily breakable, difficult to transport by hand, awkward to store, and expensive. And although metal and aluminum frames have been used in the screen print industry, these frames have been relatively expensive to make and use and are generally complex in structure. These shortcomings of commonly used print screen frames slow printing operations and cost the print screen industry time and financial resources.
The frame assembly and method of the present invention overcome the difficulties and shortcomings of prior art print screen frame assemblies by providing a lightweight, durable and inexpensive print screen frame. Electrical conduit has been used for many years in many industrial environments to protect electrical wires and cables. Electrical conduit because of its wide use is inexpensive and readily available. This invention provides a new use for this known material.
The frame structure of this invention is rigid and constructed of a strong, lightweight metal material which allows easy transportation, movement, and manipulation of the frame assembly. The frame is constructed of zinc coated metal tube material which is resistant to warping and structural weakness during prolonged printing use. The frame structure is comprised of a formed tubular conduit, coupled or welded together at each seam to form a unitary frame member.
The frame assembly further can have at least one spacer attached to the tubular frame member which allow frames to be stacked on one another and to be placed into a printing press, and which are preferably coded to identify particular frame members. For example, various spacer colors or other identifying codes may be used to identify mesh count of the screen fastened to the frame. The stacking of frames saves space and allow the print screens to dry after use. Preferably, at least one spacer is attached to the metal frame and may be detached when necessary. Each spacer has a flat bottom surface for secure placement in a press and for stacking purposes in storage. The spacers are configured to have a predetermined height for purposes of use with specified printing presses.
The frame assembly of the present invention comprises a frame constructed and arranged for use in textile print screen operations. The frame assembly is formed of electrical conduit which is readily available in a variety of lengths and diameters. The electrical conduit of the frame structure is rigid and generally constructed of a lightweight, zinc coated tubular metal material or the like. A length of tubular conduit material is formed into a desired shape and the ends of the conduit are then joined by means of an internal pressure fitting or welded or otherwise coupled together to form a unitary frame member. The frame structure may be formed of one, two or more lengths of conduit. Typically, the frame members are rectangular in structure and have rounded corners.
On one side of the frame, a taut print screen fabric is stretched and secured to the frame by means of an adhesive bond, for example. Also attached to the bottom side of the frame can be at least one spacer. After a printing screen frame has been used in a printing press, the frame assembly can rest on the floor or be stacked onto another frame assembly without contacting its fabric screen portion. Each spacer has an inner surface that conforms in shape and size to the outer surface of the frame and grips the frame conduit outer surface when snapped onto the frame. The bottom outer surface of the spacer is flat so that a frame assembly securely rests on the ground or on top of another frame assembly. This invention further relates to various printing frame structures, frame compositions, coatings, frame configurations and methods to form the frame structures.
An object of this invention is to provide an affordable and durable frame for textile screen printers. The method of manufacturing the enclosed printing frame assembly utilizes at least one length of electrical conduit, whereby the electrical conduit is bent so that the one or more lengths form a generally planar enclosure. The ends are then aligned and joined and a print screen fabric is stretched over and adhered to the frame. The frame assembly is not intended to be restretched. The frame structure can be comprised of metallic, zinc coated conduit which is resistant to warping and bowing. The frame assembly can have at least one spacer and is adapted for use in textile printing presses.
These and other benefits of this invention will become clear from the following description by reference to the drawings.